An Incremental Two-Dimensional Principal Component Analysis for Object Recognition

Table 5

Comparison of the running time on the ORL database.

	2DPCA [12]		I2DPCA		RC2DPCA [18]		IRC2DPCA
	Feature extraction time (s)	Classification time (s)	Feature extraction time (s)	Classification time (s)	Feature extraction time (s)	Classification time (s)	Feature extraction time (s)	Classification time (s)
1	0.604	0.434	0.759	0.416	0.749	0.071	1.762	0.071
2	0.984	0.420	1.352	0.416	1.158	0.071	3.050	0.065
3	1.473	0.450	1.843	0.429	1.770	0.080	4.137	0.081
4	2.261	0.433	2.360	0.419	2.551	0.086	5.800	0.079
5	2.842	0.395	2.915	0.424	3.340	0.086	7.333	0.081